JP7593635B2 - Detachable flip-up glasses - Google Patents

Description

The present invention relates to detachable flip-up eyeglasses that allow the user to selectively attach and detach a front frame, which has lenses attached separately from the eyeglass frame worn by the user, as needed, and that can also be used by flipping up the attached front frame.

Well-known eyeglasses are fitted with various lenses, such as lenses for vision correction for myopia, hyperopia, etc., lenses that block sunlight and reflected light, and lenses that magnify visual objects. Users can select and wear eyeglasses with the appropriate lenses according to their own visual acuity and intended use. However, if there are multiple visual acuity abnormalities or depending on the intended use, users must frequently change to different eyeglasses with optimal lenses. This causes inconvenience to users, as they are forced to carry multiple pairs of eyeglasses on a regular basis.

To resolve this inconvenience, glasses that have a front frame with lenses attached that are separate from the eyeglass frame worn by the user and are rotatably fixed to the eyeglass frame are known. These glasses are known as flip-up glasses, and can be used by flipping the front frame up and down (both operations will be referred to as "flip-up" below) to easily switch between the naked eye state and the state with the lens. Also, if a separate lens is already attached to the eyeglass frame, it can be used by switching between the state with a vision correction lens, for example, and the state with a sunglass lens superimposed on it.

However, even with flip-up glasses, if the strength of the lenses attached to the front frame no longer matches, or if the color or polarization of the sunglasses lenses does not suit the environment, the entire pair of glasses must eventually be replaced with glasses with different lenses. Therefore, even with flip-up glasses, the user still needs to carry multiple pairs of glasses, which leaves the problem of bulk and inconvenience.

In this regard, a technology has been disclosed for flip-up glasses in which the front frame to which the lenses are attached is detachable from the eyeglass frame. With these detachable flip-up glasses, only the replacement front frame needs to be carried, making them economical and not bulky.

For example, Patent Document 1 is a publication of a previous patent application by the applicant in which a front frame is configured to be detachable from a spectacle frame. Patent Document 1 discloses a flip-up eyeglasses technology in which the eyebrow-shaped portion of the brow bar (corresponding to the spectacle frame) and both ends of the flip-up beam (corresponding to the front frame) to which the inner frame is fixed are hinged at two points.
By configuring the flip-up beam to be hingedly connected to the brow bar at two points in this manner, the lens can be replaced (attached and detached) together with the inner frame, which has the effect of making the lens replacement work easily accessible to general users rather than specialized craftsmen.

Patent Document 2, on the other hand, is a patent publication relating to flip-up glasses with a detachable front frame that is attached by magnetic adhesion. Patent Document 2 discloses technology for flip-up glasses in which a holder member (corresponding to the front frame) on which an auxiliary lens is fixed so that it can be flipped up is fitted into the connecting part of the eyeglass body (corresponding to the eyeglass frame) so that it can be stably held by magnetic adhesion.

To give an overview of the technology of Patent Document 2, as shown in FIG. 11, the flip-up glasses 900 are made up of a glasses body 91 formed by connecting left and right frame parts corresponding to the left and right eyes, and front glasses 92. A holder member 93 is fixed to the front glasses 92, and the front glasses 92 and the glasses body 91 are detachably attached in a magnetically attracted state via the holder member 93 by a first magnetic part 94 and a second magnetic part 95. In addition, the front glasses 92 attached to the glasses body 91 are configured to be flippable via a biasing rotation device 96 provided on the holder member 93.

JP 2013-088539 A JP 2013-064787 A

However, although the technology of Patent Document 1 is configured so that the user can replace the front frame by themselves, the hinged front frame is pulled to elastically deform the connection part and remove it from the eyeglass frame. Since elastic deformation is required, a certain amount of force is required to remove the front frame. Therefore, with this technology, the user has to be careful for fear of damaging the flip-up eyeglasses themselves, and there is a problem that the front frame cannot be easily removed.
Furthermore, because the connecting parts are elastically deformed, repeated attachment and detachment can cause wear and deformation, which can lead to the connecting parts loosening and causing the front frame to come off during use.

On the other hand, the technology of Patent Document 2 is capable of removably fixing the front frame to the eyeglass frame by the action of magnetic attraction. Since there is no need to elastically deform a part of the front frame when removing it from the eyeglass frame, the user can safely pull the front frame to remove it.
However, even if the front frame is easy to attach and detach, the biasing and rotating device that acts as the rotation axis for flipping up the front frame is provided separately from the magnetic attraction part, which causes the easily visible front part of the eyeglass body or front eyeglasses to become larger and more noticeable, which causes a problem of marring the appearance.
In addition, the rotation of the flip-up relies on the sliding of the rotating shaft, and as the shaft and bearings wear out, the resistance to rotation gradually decreases, causing the flip-up front frame to drop during use. Conversely, deformation of the bearings can increase resistance, making it difficult to flip up smoothly.

The present invention was made in consideration of the above problems, and its purpose is to provide detachable flip-up eyeglasses that can reliably fix a front frame with any lens attached to an eyeglass frame, and that can be attached and detached extremely easily by the user. It is also an object of the present invention to provide detachable flip-up eyeglasses that can be flipped up with a constant resistance even if the fixed front frame is flipped up repeatedly.

The means adopted by the present inventors to solve the above problems will be described below.
The removable flip-up eyeglasses (hereinafter simply referred to as "eyeglasses") of the present invention are eyeglass frames that a user wears on his/her head or face, and a front frame on which lenses separate from the eyeglass frame are attached can be detached. The eyeglass frame includes at least left and right temples, a pair of end pieces that rotatably connect the temples, and a connecting member that connects the end pieces together. The eyeglass frame may be fitted with lenses different from the lenses attached to the front frame.

The front frame is provided with a cylindrical first magnetic body, and the eyeglass frame is provided with a cylindrical second magnetic body. The magnetic body here refers to a so-called ferromagnetic body, which is a material that can be magnetized and can attract or repel a magnet with sufficient force, regardless of the magnitude of the coercive force. In addition, both the first magnetic body and the second magnetic body are magnetized. The magnetization here refers to a state in which the magnetic body is magnetically polarized by applying an external magnetic field to the magnetic body in advance.

The front frame and the eyeglass frame can be fixed to each other by magnetic force between the first magnetic body and the second magnetic body.
To elaborate on this point, first, the front frame and the eyeglass frame can be fixed together by magnetic attraction. In other words, one magnetized magnetic body magnetically attracts the other magnetic body and continues to adhere with a constant force, so that the eyeglass frame and the front frame are integrated. The eyeglass frame and the front frame can be fixed together by maintaining this state.

The front frame fixed in this manner can be rotated and flipped up while maintaining a state in which the first magnetic body and the second magnetic body are fixed by magnetic force.
Here, the state of being fixed by magnetic force is not limited to a state in which the first magnetic body and the second magnetic body are constantly subjected to a constant magnetic force, but includes a state in which the magnetic forces acting on each other fluctuate during the process of bouncing up, so long as they are in a state in which they are mutually influenced by magnetic forces. In addition, bouncing up includes not only those that rotate upwards and bounce up, but also those that rotate downwards.

The operation of the above configuration will now be described in detail. First, since the front frame and the eyeglass frame can be fixed by the magnetic force between the first magnetic body and the second magnetic body, the front frame can be attached to and detached from the eyeglass frame without elastic deformation of any part.
In addition, when magnetic forces attract each other and fix the magnetic bodies, the magnetic bodies are attracted to each other so as to accelerate as the distance between them decreases .
In this way, no partial deformation occurs when attaching or detaching the front frame from the eyeglass frame, and the front frame is naturally guided to the fixed position when attached, so that the front frame can be easily attached without requiring careful operation.

Regarding the resistance felt during flip-up operation, the frictional force during rotation of the front frame is calculated by multiplying the coefficient of friction and the resistance (the force acting on the friction surface). Looking at resistance, in rotation using a conventional shaft and bearing, the force with which the bearing pinches the shaft becomes the resistance, but when the bearing wears and the inner diameter of the bearing expands, the resistance decreases rapidly. Also, when the bearing deforms, the inner diameter of the bearing comes into strong contact with the shaft locally, causing a sudden increase in resistance. In this way, when flip-up rotation is configured using a conventional shaft and bearing, the frictional force fluctuates over time and the resistance to flip-up cannot be maintained.

However, when the front frame is rotated while the first magnetic body and the second magnetic body are kept fixed by the magnetic force, the drag force acting on the friction surface is caused by the magnetic force. The magnetic force does not decrease due to wear, and even if the peripheral portion fixing the magnetic bodies is deformed, the magnetic force does not immediately generate a strong drag force locally.
In this way, by configuring the front frame to rotate while maintaining the first magnetic body and the second magnetic body fixed in place by magnetic force, it is possible to suppress fluctuations in resistance over time compared to a configuration using an axis and bearing.

When the front frame is flipped up, in addition to the force that rotates the front frame with the direction of attraction between the magnetic bodies as the rotation reference, a force in a direction different from the rotation reference acts because it is operated by hand. At this time, a force acts that tries to displace the first magnetic body and the second magnetic body fixed by magnetic force in a direction different from the direction of attraction .
However, because the front frame is rotated while the first and second magnetic bodies are kept fixed by the magnetic force, even if the first and second magnetic bodies try to shift in a direction different from the direction of attraction , they are pulled back to a stable position by the magnetic force. Therefore, the rotation reference is stable both before and after the flip-up operation, making it possible to flip up smoothly.

Among the means for solving the problems according to the present invention, those based on the basic configuration are as described above, but in the present invention, it is also possible to use the following means.
It is also possible that both the first magnetic body and the second magnetic body are hollow and the magnetization direction is the height direction of the cylinder.

Generally, when a magnetic body having a solid shape such as a cylinder is magnetized in the height direction, the surface magnetic flux density at the outer periphery of the end face is strongest, and the surface magnetic flux density tends to weaken toward the center. In other words, the outer periphery attracts or repels more strongly. This is the same even when a magnetic body having a hollow shape such as a cylinder is magnetized in the height direction.
Since the force of attraction due to magnetic force is proportional to the square of the surface magnetic flux density, the higher the surface magnetic flux density, the stronger the attraction. Therefore, when magnetic bodies are brought close to each other, their outer surfaces will strongly attract or repel each other.

When we look at the distribution of surface magnetic flux density on the end face, in the case of a solid shape, it gradually decreases from the outer periphery towards the center. However, in the case of a hollow shape, the surface excluding the hollow part shows a distribution where the density gradually decreases from the outer periphery towards the inside, and then increases again at the inner periphery. However, in the hollow part, especially in the center, the direction of the magnetic flux is opposite to that of the outer periphery, so the surface magnetic flux density drops suddenly. Therefore, if the external dimensions are the same, when a hollow magnetic material is used, it will be attracted or repelled by the part that is the end face excluding the hollow part.

Here, we will explain in detail the effect that the difference in the distribution of the surface magnetic flux density has when the front frame is flipped up while the magnetic bodies are attracted to each other and fixed in place. As mentioned above, if a force in a direction different from the rotation reference acts when flipping up the front frame, a force acts that tends to displace the first magnetic body and the second magnetic body, which are fixed in place by magnetic force, in a direction different from the direction of attraction.

In the case where the magnetic bodies are solid, when one of the magnetic bodies tries to shift in a direction different from the direction of attraction, the surface magnetic flux density is distributed over the entire end face, although the surface magnetic flux density varies in magnitude, so in addition to the force that attracts the outer peripheries of the end faces, a force that attracts the outer periphery of one magnetic body and the inner surface of the other magnetic body is also generated. In other words, the force that attracts the outer periphery of the end faces is offset by the force that attracts the outer periphery of one magnetic body and the inner surface of the other magnetic body. As a result, the force that firmly holds the rotation reference is weakened, and the rotation reference becomes more likely to fluctuate, which may result in a loss of smoothness in the flip-up operation.
However, when the magnetic body is hollow, the surface magnetic flux density of the polarities that are trying to attract each other is distributed on the end faces excluding the hollow part. Therefore, if one of the magnetic bodies tries to shift in a direction different from the direction of attraction, the outer periphery of the end faces and the inner periphery of the end faces try to pull each other back. On the other hand, since the surface magnetic flux density of the hollow part is extremely small, there is almost no force that tries to attract each other toward the hollow part. As a result, the force that tries to keep the position of each magnetic body constant works more strongly, making it less likely for the rotation reference to be distorted during the lifting of the front frame, making the lifting operation smoother.

Incidentally, when the front frame and the eyeglass frame can be fixed by the attraction between the first magnetic body and the second magnetic body, the front frame can be configured to be able to rotate and flip up without using shafts and bearings, using the magnetic flux lines passing through the inside of the first magnetic body and the second magnetic body in the magnetic field combined by the first magnetic body and the second magnetic body as the rotation reference when the front frame and the eyeglass frame are fixed,.
In this way, when the first magnetic body and the second magnetic body are attracted to each other, the magnetic fields of the first magnetic body and the second magnetic body are combined. At this time, if the first magnetic body and the second magnetic body have different shapes or are arranged in a misaligned manner, the magnetic flux lines passing through the inside of the magnetic body in the combined magnetic field will be distorted. Here, even if the magnetic flux lines are somewhat distorted, it is possible to rotate the front frame while maintaining the state in which the first magnetic body and the second magnetic body are fixed by magnetic force. However, by arranging the magnetic flux lines passing through the inside of the magnetic body in the combined magnetic field so that they are linear, the front frame can be rotated and flipped up more smoothly without shaking, using the linear magnetic flux lines passing through the inside of the first magnetic body and the second magnetic body as the rotation reference. Note that the rotation reference based on the linear magnetic flux lines does not necessarily have to be an axis, and may be a reference in which the magnetic flux lines rotate along a cylindrical surface in which they are parallel.

In addition, when the front frame and the eyeglass frame can be fixed by the first magnetic body and the second magnetic body attracting each other, the front frame can be rotated and flipped up while at least a portion of the first magnetic body and the second magnetic body are in contact with each other.
In this way, by rotating the magnetic bodies while they are in contact with each other, it is possible to keep the friction caused by the contact constant, and therefore the resistance felt when flipping up the magnetic body is constant.

Regarding the arrangement of the magnetic bodies, the first magnetic body may be arranged in the center of the front frame and the second magnetic body may be arranged in the center of the connecting member, and the first magnetic body and the second magnetic body may be arranged so that the longitudinal direction of the connecting member serves as the rotation reference.
By locating each magnetic body in the center, the influence on the appearance of connecting members such as the brow bar of the eyeglass frame can be minimized.

In addition, it is also possible to configure the first magnetic body by arranging it respectively at the left and right ends of the front frame and the second magnetic body respectively at the temple portions, and by arranging the first magnetic body and the second magnetic body so that the longitudinal direction of the connecting portion serves as the rotation reference.
By locating each magnetic body at the left and right ends, it is possible to prevent the left and right ends of the front frame from shaking during use. Also, when one of the lenses is pinched between the fingers to flip it up, the rotation reference is close to the position of the force point pinched between the fingers, so it can be flipped up smoothly.

In the present invention, the front frame and the eyeglass frame are fixed by the magnetic force of the first magnetic body and the second magnetic body, and the front frame can be rotated and flipped up while maintaining the fixed state. With this configuration, there is no need to elastically deform any part when attaching or detaching the front frame to or from the eyeglass frame.
In addition, when magnetic forces attract each other and the magnetic bodies are fixed, the magnetic attraction accelerates as the distance between the magnetic bodies decreases. On the other hand, when magnetic forces repel each other and the magnetic bodies are fixed, the first magnetic body and the second magnetic body are placed in a position where their magnetic forces are balanced, and are supported by the repulsive magnetic forces and attempt to maintain their positions.
As a result, the lenses are naturally guided into the fixed position during installation, making it easy to install without requiring careful manipulation. This has the effect of allowing the front frame with the desired lenses to be reliably fixed to the eyeglass frame, and allowing the user to attach and remove the lenses very easily.

In addition, by allowing the front frame to be rotated and flipped up while maintaining the first magnetic body and the second magnetic body fixed in place by magnetic force, it is possible to suppress fluctuations over time in the resistance acting between the magnetic bodies during rotation.
This has the effect that even if the front frame fixed to the eyeglass frame is repeatedly flipped up, it can be flipped up with a certain resistance.

1A and 1B are a front view and a partial plan view showing detachable flip-up eyeglasses of the present invention. FIG. 2 is a partial plan view of the eyeglass frame and front frame of the present invention. 10 is a cross-sectional view showing a state in which the front frame of the present invention is flipped up. FIG. 2 is an explanatory diagram showing magnetic flux lines of a composite magnetic field of a first magnetic body and a second magnetic body of the present invention. 1 is an explanatory diagram showing the surface magnetic flux density of a columnar and cylindrical magnetic body. FIG. 2 is a partial plan view of an eyeglass frame and a front frame according to a reference example of the present invention. FIG. 1 is an explanatory diagram showing magnetic flux lines of a composite magnetic field of a first magnetic body and a second magnetic body according to a reference example of the present invention. FIG. 2 is a partial plan view of an eyeglass frame and a front frame according to a first modified example of the present invention. FIG. 11 is a partial plan view of an eyeglass frame and a front frame according to a second modified example of the present invention. FIG. 11 is a partial plan view of an eyeglass frame and a front frame according to a third modified example of the present invention. FIG. 1 is a partial cross-sectional view showing a conventional example of Patent Document 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.
It should be noted that the magnetic flux lines in FIG. 4 and the distribution diagram of the surface magnetic flux density in FIG. 5 are shown in a simplified schematic form for the purpose of explanation.

The detachable flip-up eyeglasses 100 of the present invention (hereinafter, just referred to as "eyeglasses") are composed of a front frame 1 and an eyeglass frame 2 to which the front frame 1 is attached, as shown in FIG.
The front frame 1 has an integral resin lens 11 attached to a resin flip-up member 12. The flip-up member 12 has a portion that protrudes from the rear side, and a first magnetic body 13 is fixed to the tip.
The first magnetic body is, for example, a hollow cylindrical neodymium magnet, but may be any other type or shape of magnet, or may be a metal part that is a non-magnetized magnetic body. The lens 11 is not limited to being an integrated type, but may be separate lenses on the left and right.

The eyeglass frame 2 is composed of temples 21, 21', end pieces 22, 22' that connect the temples 21, 21' so as to be foldable and rotatable, a connecting member 23 which is a brow bar that connects the end pieces 22, 22' horizontally, and nose pads 24, 24' that hang down from the connecting member 23 to the rear side. These materials are preferably made of resin, but if they are made of metal, it is preferable that they have low magnetic properties in order to prevent magnetic influence on the first magnetic body 13 and the second magnetic bodies 25, 25'.
In addition, a pair of second magnetic bodies 25, 25' are attached to the center of the connecting member 23 at a distance approximately equal to the width of the first magnetic body 13. These second magnetic bodies 25, 25' can be cylindrical neodymium magnets like the first magnetic body 13, but when a magnet is used for the first magnetic body 13, the second magnetic bodies 25, 25' can be metal parts that are unmagnetized magnetic bodies.

When the first magnetic body 13 and the second magnetic bodies 25, 25' are both magnets, the second magnetic bodies 25, 25' are arranged so that the opposing faces have different polarities. Also, the first magnetic body 13 is arranged so that the opposing faces have different polarities when inserted into the gap between the second magnetic bodies 25, 25'.

When attaching the front frame 1 to the eyeglass frame 2, the first magnetic body 13 of the front frame 1 is brought closer to the second magnetic bodies 25 and 25' of the eyeglass frame 2 so as to be inserted into the gap between them, as shown in Fig. 2. When the first magnetic body 13 and the second magnetic bodies 25 and 25' are gradually brought closer to each other and reach a predetermined distance, the opposing surfaces of the first magnetic body 13 and the second magnetic bodies 25 and 25', which have different polarities, attract each other. As a result, the front frame 1 and the eyeglass frame 2 are held in a fixed state as shown in Fig. 1.
At this time, even if the first magnetic body 13 of the front frame 1 is brought close to a position slightly shifted from the gap between the second magnetic bodies 25, 25', the first magnetic body 13 and the second magnetic bodies 25, 25' attract each other, so that the first magnetic body 13 is naturally attracted to the gap between the second magnetic bodies 25, 25'. Therefore, the user can easily fix the front frame 1 to the eyeglass frame 2.

The front frame 1 fixed to the eyeglass frame 2 by magnetic force can be bounced up using the first magnetic body 13 and the second magnetic bodies 25 and 25' as rotation bases, as shown in FIG.
Here, the first magnetic body 13 and the second magnetic body 25, 25' are arranged so that the central axes of the magnetic bodies are aligned. Even during rotation, the end faces of the first magnetic body 13 and the second magnetic body 25, 25' are attracted to each other by magnetic force and are in close contact and fixed. In this state, the magnetic fields of the first magnetic body 13 and the second magnetic body 25, 25' are combined to form a magnetic field represented by magnetic flux lines as shown in FIG. 4.

In this state where the first magnetic body 13 and the second magnetic body 25, 25' are in close contact and fixed, linear magnetic flux lines are generated in the combined magnetic field, penetrating the insides of the first magnetic body 13 and the second magnetic body 25, 25'. These linear magnetic flux lines are generated evenly in the circumferential direction, and therefore form a cylinder. When the front frame 1 is flipped up, it rotates with the cylindrical magnetic flux lines formed by these linear magnetic flux lines as the rotation reference. In other words, it rotates along the circumferential surface of the cylinder formed by the magnetic flux lines.
This linear magnetic flux line is maintained even if the first magnetic body 13 and the second magnetic bodies 25, 25' rotate relative to each other, and if the rotation reference tries to shift, the magnetic force tries to pull the magnetic body back, allowing for a smooth bounce without disturbing the rotation reference.

Here, when a solid cylindrical magnet 3 and a hollow cylindrical magnet 4 of the same outer diameter and height are magnetized in the height direction, the distribution of surface magnetic flux density at the end faces generally looks like that shown in Figures 5(a) and (b).
In the case of a cylindrical shape, as shown in FIG. 5(a), the surface magnetic flux density is highest at the outer periphery 31 and gradually decreases toward the center 32. On the other hand, in the case of a cylindrical shape, as shown in FIG. 5(b), the surface magnetic flux density is also highest at the outer periphery 41, but gradually decreases toward the inner periphery 43, where it increases again. However, in the hollow portion 42, especially in the center 32, the direction of the magnetic flux is opposite to that of the outer periphery 41, so the surface magnetic flux density drops sharply. Here, if the magnets are the same size and the residual magnetic flux density is also the same, the peak value of the surface magnetic flux density is lower in the cylindrical shape than in the cylindrical shape. However, when a cylindrical magnet is used as shown in FIG. 5(b), the surface magnetic flux density of the polarity of attraction is distributed in the end face except for the hollow portion 42.

When a cylindrical magnet 4 with such characteristics is used for the first magnetic body 13 and the second magnetic bodies 25, 25', if a force acts to move them in a direction different from the direction of attraction when they are flipped up, the outer periphery 41, 41 of the end faces and the inner periphery 43, 43 of the end faces will try to pull them back together, but since the surface magnetic flux density of the hollow portion 42 is extremely small, there is almost no force that attracts them towards the hollow portion 42. This makes it less likely for the rotational reference to deviate while the front frame 1 is being flipped up, making the flip-up operation smoother.

『 Reference Example 1』
Next, a reference example of the eyeglasses of the present invention will be described with reference to Fig. 6 and Fig. 7. In the following description, the same parts are designated by the same reference numerals, and duplicated descriptions will be omitted. It should be noted that the magnetic flux lines in Fig. 7 are simply and diagrammatically illustrated for the purpose of explanation.

In this reference example , the basic configuration of the front frame 1 and the eyeglass frame 2 is the same as that of FIG. 1. However, the first magnetic body 13 is different in that it has a smaller diameter than the second magnetic bodies 25 and 25'. The first magnetic body 13 is also different in that it is arranged so that the opposing faces of the first magnetic body 13 have the same polarity when inserted into the gap between the second magnetic bodies 25 and 25'. When the first magnetic body 13 is arranged in this way, the first magnetic body 13 and the second magnetic bodies 25 and 25' repel each other.

When attaching the front frame 1 to the eyeglass frame 2, as shown in Fig. 6, the first magnetic body 13 of the front frame 1 is brought closer to the second magnetic bodies 25 and 25' of the eyeglass frame 2 so as to be inserted into the gap between them. When the first magnetic body 13 and the second magnetic body 25 and 25' are gradually brought closer to each other and reach a certain distance, the opposing surfaces of the first magnetic body 13 and the second magnetic body 25 and 25', which have the same polarity, repel each other, and the closer they are, the stronger the repulsive force becomes. However, when the first magnetic body 13 is pushed into the gap between the second magnetic bodies 25 and 25' against the repulsive force, the first magnetic body 13 is contained between the second magnetic bodies 25 and 25' and its position is maintained because the diameter of the first magnetic body 13 is smaller than the diameter of the second magnetic bodies 25 and 25' and the surface magnetic flux density of the hollow part is sandwiched between the parts of the inner periphery 43 and 43 with high surface magnetic flux density and distributed like a valley, as described later.
In this configuration, the balance of the magnetic forces is easily lost, so it is preferable to have the eyeglass frame 2 and the flip-up member 12 partially abut against each other so that they are always positioned before and after flip-up.

At this time, as shown in Fig. 7, the magnetic flux lines generated by the first magnetic body 13 are balanced while being repelled by the magnetic flux lines generated by the second magnetic bodies 25 and 25'. That is, the magnetic bodies repel each other at the inner periphery 43 in Fig. 5(b), and the magnetic forces are balanced.
In this balanced state, if a force acts to displace the front frame in a direction different from the repulsive direction when the front frame is flipped up, the magnetic bodies will come closer to each other, the repulsive force will become stronger, and the front frame will be pushed back. This makes it harder for the rotation reference to deviate while flipping up the front frame 1, making the flip-up operation smoother.

『 Variation 1 』
Another modified example of the eyeglasses of the present invention will be described with reference to FIG.
In this modification, the front frame 1 is provided with two first magnetic bodies 13, 13', and the eyeglass frame 2 is provided with two second magnetic bodies 25, 25'. Here, the first magnetic body 13 and the second magnetic body 25 on the left side as viewed from the front are arranged so that their different polarities face each other so as to attract each other. The first magnetic body 13' and the second magnetic body 25' on the right side as viewed from the front are also arranged so that their different polarities face each other so as to attract each other.

Both the first magnetic body 13, 13' and the second magnetic body 25, 25' use cylindrical neodymium magnets, but one edge of the hollow part is chamfered for mounting a flat head screw. A flat head screw is inserted into this chamfer. That is, flat head screws 14, 14' are inserted into the first magnetic body 13, 13' and screwed to the front frame 1, and flat head screws 26, 26' are inserted into the second magnetic body 25, 25' and screwed to the eyeglass frame 2.

In this way, when cylindrical neodymium magnets are used for the first magnetic body 13/13' and the second magnetic body 25/25', the hollow portions can be used for screw fixing to reliably fix the first magnetic body 13/13' to the front frame 1 or the second magnetic body 25/25' to the eyeglass frame 2. It is preferable to use plastic screws for the countersunk screws 14/26, as they do not affect the magnetic field.

" Variation 2 "
Another variation of the eyeglasses of the present invention is one in which a cubic or rectangular parallelepiped neodymium magnet is used for the second magnetic body 25, 25' of the eyeglass frame 2, as shown in Fig. 9. The cubic or rectangular parallelepiped second magnetic body 25, 25' is inserted into an insertion groove provided on the central rear side of the eyeglass frame 2 and adhesively fixed thereto.

If the second magnetic bodies 25, 25' are cylindrical or columnar, when the front frame 1 is flipped up, the magnetic attraction force may cause the second magnetic bodies 25, 25' to rotate together with the first magnetic body 13, and the second magnetic bodies 25, 25' may fall off during use.
However, by using a cubic or rectangular neodymium magnet, even if the front frame 1 is repeatedly flipped up, the corners of the cube or rectangular parallelepiped will engage with the corners of the insertion groove of the eyeglass frame 2, preventing it from rotating.

『 Variation 3 』
Another example of a variation of the eyeglasses of the present invention is one in which two first magnetic bodies 13, 13' are provided at the left and right ends of the front frame 1, and two second magnetic bodies 25, 25' are provided at the left and right end pieces 22, 22', as shown in Fig. 10. In this case, the first magnetic body 13 and the second magnetic body 25 on the left side as viewed from the front are also arranged so that their different polarities face each other so as to attract each other. The first magnetic body 13' and the second magnetic body 25' on the right side as viewed from the front are also arranged so that their different polarities face each other so as to attract each other.

By providing the first magnetic bodies 13, 13' and the second magnetic bodies 25, 25' at the left and right ends in this manner, there is no need to place a complex structure around the bridge, and the appearance is improved.
In addition, when flipping up, one of the lenses 11 and 11' is pinched with the fingers of one hand and flipped up. Therefore, if the magnetic bodies that serve as the rotation reference are provided on the left and right ends, the rotation reference that serves as the fulcrum is closer to the point of force pinched with the fingers, and the flip-up operation can be performed more smoothly.

The present invention is not limited to the above embodiment, and for example, a yoke for magnetic induction may be arranged around the magnetic body to concentrate the magnetic force and fix it more firmly, or a magnetic shield may be provided to prevent unnecessary radiation of magnetism. Furthermore, the first magnetic body and the second magnetic body may be arranged not only in the center or at the left and right ends, but also at the center upper part of the left and right lenses.
Furthermore, the first magnetic body and the second magnetic body may be disposed at the lower portion and used as a rotation reference, and the front frame may be rotated downward.
In addition, the first magnetic body and the second magnetic body may each be composed of one each, and the surface opposite to the surface that is attracted or repelled by magnetic force may be configured to be pressed against a part of the front frame or the eyeglass frame to be fixed.

100 Detachable Glasses 1 Front Frame
11 Lens
12 Lifting member
13 The First Magnetic Body
14 Flat head screws 2 Glasses frames
21 Temple
22 Tomobe
23 Connecting members
24 Nose pad
25 Second Magnetic Body
26 Flat head screw 3 Cylindrical magnet
31 Outer periphery
32 Center 4 Cylindrical magnet
41 Outer periphery
42 Hollow section
43 Inner circumference

Claims (3)

In a detachable flip-up eyeglasses, a front frame having a lens separate from the eyeglass frame is detachably attached to an eyeglass frame having at least left and right temples, a pair of end pieces rotatably connecting the temples, and a connecting member connecting the end pieces,
The front frame is provided with a cylindrical first magnetic body, and the eyeglass frame is provided with a cylindrical second magnetic body,
Both the first magnetic body and the second magnetic body are hollow and magnetized in the height direction of a cylinder ,
the front frame and the eyeglass frame can be fixed to each other by the magnetic force between the first magnetic body and the second magnetic body,
The detachable flip-up eyeglasses are characterized in that, in a state in which the front frame and the eyeglass frame are fixed, while the first magnetic body and the second magnetic body are maintained in a fixed state by magnetic force, the front frame can be rotated and flipped up without using an axis or bearings, using as a rotation reference a magnetic flux line passing through the inside of the first magnetic body and the second magnetic body in a magnetic field synthesized by the first magnetic body and the second magnetic body . the first magnetic body is disposed in a central portion of the front frame, and the second magnetic body is disposed in a central portion of the connecting member,
2. The detachable flip-up eyeglasses according to claim 1 , wherein the first magnetic body and the second magnetic body are arranged so that a longitudinal direction of the connecting member serves as a rotation reference. The first magnetic bodies are disposed at the left and right ends of the front frame, respectively, and the second magnetic bodies are disposed at the end portions, respectively;
2. The detachable flip-up eyeglasses according to claim 1 , wherein the first magnetic body and the second magnetic body are arranged so that a longitudinal direction of the connecting member serves as a rotation reference.

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